1. Field of the Invention
The present invention relates to the overlay of virtual entities on a real-world environment.
2. Background Art
Virtual reality (VR) is a technology which allows a user to interact with a computer-simulated environment. Virtual reality is typically presented to a user as a visual experience, displayed either on a computer screen or through special (e.g., stereoscopic) displays. Some virtual reality systems may include additional sensory information, such as sound provided through speakers or headphones, and/or tactile information. Users can interact with a virtual environment or a virtual artifact (VA) through the use of standard input devices such as a keyboard and mouse, or through multimodal devices such as a wired glove, a Polhemus boom arm, or an omnidirectional treadmill.
A virtual reality environment can be similar to the real world. For example, virtual reality environments include simulations for pilot or combat training. Alternatively, a virtual reality environment can differ significantly from reality. For instance, virtual reality environments include games and alternate world simulations (e.g., a simulation of a medieval world).
In virtual reality techniques that provide a visual experience to the user through a computer screen or special display, only virtual entities are included in the provided virtual experience. In other words, the visual experience provided to the user is entirely virtual. Real world entities in the field of view of the user are not included in the provided visual experience. What is desired are ways of including both real world entities and virtual reality entities in a virtual reality experience provided to users.